Engine Crashes When Building Lighting if Precomputed Visibility Aggressiveness is set to VIS Max

The engine crashes when building lighting if World Settings >> Precomputed Visibility >> Visibility Aggressiveness is set to "VIS Max."
A Fatal Error message sometimes appears (screen shot attached) before the editor closes.
This occurs in 4.18. I tested in 4.17 but "VIS Max" is not a selectable option in 4.17 and selecting the other settings (least/moderately/most aggressive) and then building the lighting does not result in a crash.

1. Open new default level
2. In World Settings, change Precomputed Visibility Aggressiveness to "VIS Max."
3. Build Lighting
   Result: Editor Crash

LoginId:77ac66cf4b506a51a458c382c4ec63c2
EpicAccountId:5caf2c99925243e8b9b1bdcc9cd0e6cf

Access violation - code c0000005 (first/second chance not available)

UE4Editor_Core!FConfigCacheIni::GetString() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\core\private\misc\configcacheini.cpp:1902]
UE4Editor_Core!FConfigCacheIni::GetFloat() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\core\private\misc\configcacheini.cpp:2267]
UE4Editor_UnrealEd!FLightmassExporter::WriteSceneSettings() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\lightmass\lightmass.cpp:2105]
UE4Editor_UnrealEd!FLightmassExporter::WriteToChannel() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\lightmass\lightmass.cpp:581]
UE4Editor_UnrealEd!FLightmassProcessor::InitiateExport() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\lightmass\lightmass.cpp:2612]
UE4Editor_UnrealEd!FStaticLightingSystem::InitiateLightmassProcessor() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\staticlightingsystem\staticlightingsystem.cpp:2041]
UE4Editor_UnrealEd!FStaticLightingSystem::BeginLightmassProcess() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\staticlightingsystem\staticlightingsystem.cpp:703]
UE4Editor_UnrealEd!FStaticLightingManager::CreateStaticLightingSystem() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\staticlightingsystem\staticlightingsystem.cpp:303]
UE4Editor_UnrealEd!UEditorEngine::BuildLighting() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\staticlightingsystem\staticlightingsystem.cpp:2301]
UE4Editor_UnrealEd!FBuildAllHandler::ProcessBuild() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\editorbuildutils.cpp:1025]
UE4Editor_UnrealEd!FEditorBuildUtils::EditorBuild() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\unrealed\private\editorbuildutils.cpp:427]
UE4Editor_LevelEditor!FLevelEditorActionCallbacks::Build_Execute() [d:\build\++ue4+release-4.18+compile\sync\engine\source\editor\leveleditor\private\leveleditoractions.cpp:635]
UE4Editor_LevelEditor!TBaseStaticDelegateInstance<void __cdecl(void)>::ExecuteIfSafe() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:1027]
UE4Editor_Slate!FUICommandList::ExecuteAction() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\framework\commands\uicommandlist.cpp:97]
UE4Editor_Slate!SToolBarButtonBlock::OnClicked() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\framework\multibox\stoolbarbuttonblock.cpp:300]
UE4Editor_Slate!TMemberFunctionCaller<SToolBarButtonBlock,FReply (__cdecl SToolBarButtonBlock::*)(void) __ptr64>::operator()<>() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\core\public\delegates\delegateinstanceinterface.h:165]
UE4Editor_Slate!UE4Tuple_Private::TTupleImpl<TIntegerSequence<unsigned int> >::ApplyAfter<TMemberFunctionCaller<SToolBarButtonBlock,FReply (__cdecl SToolBarButtonBlock::*)(void) __ptr64> >() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\core\public\templates\tuple.h:497]
UE4Editor_Slate!TBaseSPMethodDelegateInstance<0,SToolBarButtonBlock,0,FReply __cdecl(void)>::Execute() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:327]
UE4Editor_Slate!TBaseDelegate<FReply>::Execute() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:537]
UE4Editor_Slate!SButton::OnMouseButtonUp() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\widgets\input\sbutton.cpp:282]
UE4Editor_Slate!<lambda_1002768c627006711ef2f351a87ec0e7>::operator()() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5263]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_1002768c627006711ef2f351a87ec0e7> >() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:234]
UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5252]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5750]
UE4Editor_Slate!FSlateApplication::OnMouseUp() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5730]
UE4Editor_ApplicationCore!FWindowsApplication::ProcessDeferredMessage() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:1725]
UE4Editor_ApplicationCore!FWindowsApplication::DeferMessage() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:2171]
UE4Editor_ApplicationCore!FWindowsApplication::ProcessMessage() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:888]
UE4Editor_ApplicationCore!FWindowsApplication::AppWndProc() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:725]
user32
user32
UE4Editor_ApplicationCore!FWindowsPlatformApplicationMisc::PumpMessages() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\applicationcore\private\windows\windowsplatformapplicationmisc.cpp:129]
UE4Editor!FEngineLoop::Tick() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:3220]
UE4Editor!GuardedMain() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\launch\private\launch.cpp:166]
UE4Editor!GuardedMainWrapper() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:134]
UE4Editor!WinMain() [d:\build\++ue4+release-4.18+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:210]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:253]
kernel32
ntdll